Category : Dbase (Clipper, FoxBase, etc) Languages Source Code
Archive   : ASMFILE.ZIP
Filename : NUM_DRVS.ASM

;
;****************************************************************
; *
; CLIPPER ROUTINE - RETURN NUMBER OF LOGICAL DRIVES *
; By Kelly Mc Tiernan *
; *
;****************************************************************
;
;
; This routine returns the number of logical drives available
; on the machine in question. Call with 2 byte string, returns
; ascii 2 digit value equal to the number of logical drives.
; use VAL() to convert to numeric.
;
; NDRV = " "
; CALL NUMDSK WITH NDRV
; N = VAL(NDRV)
;
PUBLIC numdsk
;
dos EQU 21h ; DOS interupt
seldsk EQU 0Eh ; select disk function
curdsk EQU 19h ; return currently selected disk
;
_PROG SEGMENT BYTE
ASSUME CS:_PROG
;
numdsk PROC FAR
push bp ; standard setup, param's
mov bp,sp ;
push es ;
cld ; assure direction
les di,dword ptr [bp + 6] ; address of return string
mov ah,curdsk ; get currently selected disk
int dos ;
mov dl,al ; reselect it to get number
mov ah,seldsk ; of logical drives
int dos ;
mov ah,0 ; for conversion to ascii string
aam ; al -> (ascii) ax = aam + 3030h
add ax,3030h ;
xchg ah,al ; for stosw, i.e. - LB,HB reverse
stosw ; return number of logical drives
pop es ; restore state
pop bp ;
ret
numdsk ENDP
_PROG ENDS
END